S = int(input())
if S >=30:
    print('Yes')
else:
    print('No') S = int(input()) S int(input()) int input() input if S >=30:
    print('Yes')
else:
    print('No') S >=30 S 30 print('Yes') print 'Yes' print('No') print 'No' S = int(input()) int(input()) S
S = int(input())
if S >=30:
    print('Yes')
else:
    print('No')